Finished textile and method of producing same



United States Patent "cc 3,140,197 FINISHED TEXTILE AND METHOD OF PRODUCING SAME Georg Heberlein, Fritz Munzel, and Werner Kunz, Wattwil, Switzerland, assignors to Heberlein & Co. AG., Wattwil, Switzerland, a corporation of Switzerland NoDrawing. Filed -Mar. 31, 1960,-Ser. No...62,068 Claims priority, application switzerland Apr-.1, 1959 8 Claims. (Cl.-117- 93.31)

This invention relates to an improved method of finishing textiles to impart dimensional stability and creaseresistance thereto. It is particularly directed to a method of finishing a textileformedfrorn natural or regenerated cellulose, and is especially adapted for imparting wash and wear properties to cellulosic textile materials. This invention is also directed to a finished natural or regenerated cellulose textile product characterized by a high resistance to creasing, excellent dimensional stability by a higher abrasion resistance than the unfinished textile.

The term textile as employed herein shall be understood to include textile materials of all kinds, including fibers, yarns, threads, and woven as well as non-woven fabrics and knitted goods.

It is known that in order to improve the crease-resistant properties of natural or regenerated cellulose fabrics, for example, cotton or rayon or mixed cotton and rayon goods, the'fabric is impregnated with one or more well known condensable substances, for example, a synthetic resin precondensate, which is dispersed or dissolved in a carrier which also contains a condensation catalyst. Following irnpregnation, the excess resin is squeezed out and the impregnated fabric is then subjected to elevated temperatures, above 100 C., for a period of time sufficient to condensethe resin. This technique is conventional in the art and is so referred to hereinafter. Cellulosic textiles finished in the conventional manner with the aid of elevated temperature are generally speaking substantially less durable than the unfinished or starting fabric. For example, the conventional finishing method imparts acceptable crease-resistance, but at the expense of a marked reduction in the fiber strength of the textile product, as evidenced by either-an appreciably reduced tensile strength or resistance to abrasion or both.

It is an object of the present invention to provide a method for finishing cellulosic textile materials which does not employ elevated temperature to effect condensation of the condensable finishing substance on the textile. It is a further object to produce a dimensionally stable cellulosic textile having excellent crease-resistant properties without adversely affecting the tensile strength or abrasion resistance of the goods. It is another object of the present invention to provide a novel resin-finished textile of superior tensile strength and abrasion resistance than the conventional thermally condensed resin-finished textile.

In accordance with the method of the present invention it has now been found that cellulosic textiles, especially flat shaped fabrics, can be finished in an improved manner, without resort to the elevated temperatures. of the conventional process, by first treating the textile with a condensable substance and then subjecting the treated textile to the influence of ionizing radiation, more particularly to electromagnetic ionizing radiation, namely 3,140,197 Patented July 7, 1964 gamma radiation or X-rays, whereby the condensable substance is condensed on the textile.

The terms condensable substance and resin precondensate are employed interchangeably herein and are to be understood as meaning a substance which can be condensed with itself and with cellulose; these terms may also refer to a mixture of two or more substances which may intercondense. These condensable substances are those customarily employed in the crease-proof finishing of cellulosic textiles, and are well known cross-linking or resin-forming substances, for example, methylol ureas, methylol amines, precondensates of formaldehyde with phenol and phenol derivatives, ketone-aldehyde precondensates, azin'dinyl compounds, diglycide ethers. Other suitable resin-forming-substances are N-substituted urea formaldehyde resin compositions such as ethylene urea, dioxy ethylene urea or N,N'-bis (methoxy-methyl) uron and tetrahydro-l,3 -bis (methoxymethyl)-5-methyl- 2(1)-s-triaz0ne as described inUnited States Patent No. 2,373,135. Mixtures of two or more'condensable substances may be employed if desired, as pointed out hereinafter by Way of example.

In many instances the present method permits condensation of the resin-precondensate without resort to a catalyst, which is highly desirable since the cross-linking or condensing catalysts employed in the conventional process (e.g., metal halides, zinc nitrate, boron trifiuoride, etc.) are acidic and adversely atfect the cellulose. Whenever a catalyst is employed it is of course necessary to thoroughly Wash the textile in order to prevent damage to the cellulosic fibers. In some instances of the present method, after-Washing may thus be eliminated.

The condensable substance is applied to the cellulosic textile in the form of a solution or dispersion in water or an organic solvent, depending upon its nature and solubility. Impregnation of the textile is carried out in substantially the same manner as in the conventional finishing process, although with thepresent invention the squeezed-out textile may or may not be: dried prior to irradiation, if desired.

The total irradiation dose to which'the impregnated fabric is subjected will depend upon the condensable substance with which the textile has been impregnated, with due carebeing taken to avoid any appreciable damage to the cellulose molecule. The time required to effect condensation will of course depend upon the energyv of the radiation source, and accordingly we specifiy herein a total dose in roentgen units (r.) to which the. impregnated textile is subjected. We have found that a does of at least 10 r..is required, and thatthe .dose should not exceed about 10" r. If the textile is-subjected to'more than about 10' r. serious degradation of the cellulose molecular structure results. Excellent results are obtained by irradiating the impregnated textile with gamma 0r X-rays to a total dose of between about 0.5 X10 and about 3X10 r. The irradiation may be carried out at room temperature, for example between about 15 and 25 C.

The most convenient sources of gamma-rays, the preferred electromagnetic ionizing radiation, are C0 burnt uranium slugs, fission products of U separatedisotopes, such as Cs etc.

The method of the present invention employing electromagnetic ionizing radiation is not to be confused with prior attempts by others to treat textiles which have been impregnated with condensable substances with high energy electron beams (beta particles) produced by high voltage accelerating apparatus, for example, to effect condensation. As a result of such a treatment with particles of an energy above about 1 mev. the cellulosic fibers which make up. the textile are subjected to excessive degradation. In accordance with the present invention, on the other hand, the dose of ionizing radiation is relatively much smaller, so small that any decrease in strength or stability of the cellulosic fibers due to irradiation in negligible. As a practical matter, in nearly every instance the product of this invention exhibits a higher tensile strength and resistance to abrasion than the starting or unfinished textile. The reasons for this enhancement of the finished textile are not yet fully apparent, but may be in connection with cross linking between resin and cellulose, although we do not wish to be bound by that hypothesis. While this invention is applicable to the treatment of cellulosic textiles of all kinds to impart crease-resistance and dimensional stability thereto, its electromagnetic ionizing radiation-induced condensation is also suitable for producing permanent effects in or on a textile fabric, for example, embossing effects such as goffering, ribbing, schreiner or moire effects, as well as calendering effects, produced with or without friction.

The present method is also eminently well suited for imparting a high degree of crease-resistance to parchmentized or transparentized natural or regenerated cellulose fabrics. As is known, a cellulosic fabric upon treatment with concentrated sulphuric acid becomes stiff and transparent. Similar effects can be obtained by treating the fabric with a cuprammonium solution or a sodium zincatecellulose solution. However, attempts to render such transparentized fabrics crease-resistant by condensing a resin precondensate thereon at temperatures of 100 C. and above in the conventional manner have resulted in a commercially untenable reduction in the strength of the fibres of the fabric which are already somewhat brittle by reason of the transparency treatment. If the transparentized fabrics are subjected to electromagnetic ionizing radiation in accordance with the present invention the resin precondensate is effectively condensed, and the resulting fabric product exhibits good crease resistance without any noticeable reduction in the strength of the fibers, that is, without any reduction in the tensile strength or abrasion resistance of the transparentized goods.

The invention is described in further detail in the following non-limiting examples which illustrate practical applications of the method, and describe certain characteristics of the novel finished textile products.

Example 1 A cotton imitation poplin with 36/19 threads per French inch and English yarn numbers 40/30 in the warp and filling was singed, desized and bleached. It was then impregnated with a solution of 100 g. of dimethylol urea dissolved in one liter of water to which there was also added 11 g. of zinc nitrate catalyst. The fabric was then squeezed out and dried for twenty minutes at 60-70 C. It was then subjected to gamma radiation at C. to a total dose of about 1 10 r. Co having a radiation intensity of 3.8 10 r. per hour was employed as the source of gamma rays. Following irradiation the fabric was washed and dried. The finished cotton cloth had a pleasantly soft hand.

The crease resistance of the finished fabric was determined by measuring crease angles as follows: Strips of the fabric 3 x 5 cm. conditioned for twenty-four hours at 21 C. and 65% relative humidity. They were thereupon folded in the warp or filling direction, respectively, and placed under a 1 kg. weight for one hour. Upon removal of the weight, the fabric samples were left unweighted for fifteen minutes and the crease angle thereupon measured.

The tensile strength of the fabric was measured with a Schopper pendulum apparatus on strips 2.5 cm. wide. Abrasion resistance was measured With a standard testing apparatus containing a disc covered with a standardized wool cloth which was rotated on the surface of the fabric until the fabric failed, and the number of revolutions to failure was noted.

The warp and filling crease angles, tensile strength and abrasion strength of the unfinished and finished fabric along with values for the same fabric which was finished in the conventional manner with the same condensable substance, but with condensation being effected by subjecting the fabric to a temperature of 140 C. for five minutes, are reported below Conven- Unfinished Finished tionnlly Finished 44 107 113 40 114 23 30 14. 5 Abrasion (revs) 15,000 43, 000 3,170

Example 2 A desized mercerized bleached cotton poplin fabric was impregnated with a 10% aqueous solution of a triazone derivative of the following formula:

Inc on,

Unfinished Finished Warp angle (deg) 45 81 Filling angle (deg.) 56 79 Tensile (kg) 22. 8 21.7 Abrasion (revs) 15, 800 16,100

Example 3 A cotton longcloth which had been pre-treated in the customary manner was impregnated With a 15% aqueous solution of aziridinyl phosphonium oxide of the following formula:

H CTCH CH1 N IIZC The solution also contained 15% of 65 boron trifluoride dihydrate (calculated on the aziridinyl compound) as catalyst, as well as 7.5% of 10% octadecylethyleneurea emulsion (calculated on the aziridinyl compound) as a plasticizer. Following impregnation the fabric was dried for ten minutes at 60-70 C., and then subjected to the source of gamma radiation of Example 2 at 20 C. to a total dose of about 1 10 r. The finished fabric had a pleasantly soft hand and was substantially flame-proof.

Crease angles and values for tensile and abrasion strengths of the unfinished and finished fabric, as well as for a conventionally finished fabric (condensation having been effected by subjecting the impregnated cloth to temlowed by drying the dimensions of the finished fabric did not change for practical purposes.

The crease angles and tensile and abrasionstrengths of the unfinished and finished fabric were as-follows:

perature of 140 C.-for a 'period of five minutes) were as follows: -Unfinished Finished Conven- Warp angletdeg.) 47 105 Unfinished Finished tionally Filling angle (deg.).- V 40 95 Finished Tensile (kg) 13 13 V Abrasion (revsl) 12,000 16,000

Warp angle (deg) .L 49 105 89 Filling tingle (deg 59 101 95 Example 6 Tensile (kg,) 20 21 15.2 Abram (IBVSJ 10,000 151500 121800 Spun rayon gabardine was impregnated with an aqueous solution of a urea-formaldehyde precondensate con- Example 4 taining 10% 'MgCl 'iH O and an equal weight of a A partially Water Soluble diepoxide compound is silicone emulsion (both magnesium chloride and silicone pared byinteractionof glycerol monochlorhydrin and emulslon belng calculated'on' the welght of urea-formalchlorhydrin. An emulsion is formediby mixing'l00 grams dehyde pre'condens ate) The fabnc. was i Squeeze? of this diepoxide compound, 100 grams of a5% polyvinyl out to 9 and Wlthout furthgr y i Sublected at 20 alcohol solution and 20 grams of a 20% dispersion of a to g to a toial g mf (1.036 of about polyethylene softener. To this emulsion are added 12.5 (18x10 ponpwmg lrradlanon the fabnc wisfinany grams of a 40% solution of zinc borofluoride; water is under tenslon' It had Pleasantly p h then added with intense stirring to make a liter of emul- T e creiase angle and lensfle abraslon Strengt S sion 25 of the finished and unfinished fabric were as follows:

Cotton poplin was impregnated with this dispersion, 'and then subjected, without preliminary drying, to C0 Unfimshed .Fmlshed to a total dose of gamma radiation equal to about 1x10 r. W (d Irradiation wascarried out at 23 C. Following irradia- P angle 69) 45 F ll 1 d 4a 110 month: fabrlc was washed and drled. The finlshed fabric w en 'iie fi fifuii 23 34 was found to be absolutely resistant to chlorine washing, Abrasmn (W59 14,000 19,000

andthequantity of resin on the fabric was not affected by repeated immersions in boiling water.

Creaseangles and tensile and abrasion strengths of the unfinished and finished fabric, as well as those for the same-fabric conventionally finished With the same resins which were condensed by subjecting the impregnated fabric to a temperature of 140 C. for five minutes, were as follows:

Conven- Unfinished Finished tionally Finished Warp angle (deg) 48 95 70 Filling angle (deg.) 45 92 S3 Tensile (kg) 2 .43 15.5 Abrasion (revs.) 12, 000 17, 000 8, 990

FINISHED FABRIC AFTER WASHING Warp angle (deg) 91 Filling angle (deg.-) 95 Tensile (kg.) 42

Abrasion (revs) 16,000

Example 5 A dispersion was prepared which contained 100 g. of a 5% polyvinyl alcohol solution, 25 g. of a nonionic plasticizer, 75 g. of the diepoxide of Example 4, 60 g. of a 50% solution of dimethylolethyleneurea and 13 g. of a zinc boronfiuoride solution in 750 g. of water. A fabric containing warp and filling yarns of 70% cutton-30% spunirayon, which had been pretreated'in the customary manner and mercerized was impregnated with the aforementioned dispersion and squeezed out to 85%. Thereupon, the fabric was dried for thirty minutes at 50 C. and irradiated at 18 C. with Co to a total gamma radiation dose of about 1.3 X 10 1. Upon washing with 5 g. per liter soap at 60 C. in a washing machine fol- The textile materialsof Examples 1-.6 areconsidered light to medium weight fabrics, and in each instance the finished product still-retained a-pleasantly soft hand.

While the treating conditions set forth in Examples 1-6 are not offered as optimum, but simply as illustrative of the present method, nevertheless, examination of the crease angles, tensile and abrasion strengths reported for each of the six products clearly shows the markedly improved crease-proof properties of the finished goods as well .as the marked improvement in resistance to abrasion as compared with-the unfinished material. Furthermore, in nearly every instance the tensile strength of the unfinished goods is very significantly increased. Tensile strength is never substantially; reduced.

In Examples 1, 3 and 4 comparisons of thepresent product with that produced by the conventional method are given. Tensile and abrasion strengths of the present product are materially higher than for the conventional product, with substantially the same or a greater improvement in the crease angles.

Example 7 A bleached mercerizecl cotton-make yarn of English yarn number 60/2 was. impregnatedwith an aqueous.solution containing 70 g. of dimethylolethyleneurea and 10 g. of zinc nitrate per liter, dried-at 60 C.-and then subjected at 20 C. to gamma radiation from C0 to a total dose of about l l0 r. The finished yarn is eminently well suited for embroidery and has less tendancy to shrink than the unfinished yarn or yarn finished by the conventional method.

Example 8 A cotton muslin of 29/19 threads per A French inch and English yarn number /102 in the warp and filling was mercerized and bleached in the usual manner. It was then treated with 50.7" B. sulfuric acid at 15 C. for seven seconds, washed with water, after-mercerized with 30 B. caustic. soda for fifteen seconds, then washed neutral in cold water'and dried under tension. This pretreatment produced a transparentized fabric, which was then impregnated with a solution of g. 'of dimethylolethyleneurea dissolved in one liter of water to which had been added 11 g. of zinc nitrate. The transparentized fabric was then squeezed out and dried for twenty minutes at 60-70 C. The thus transparentized, impregnated dried goods were then subjected at 20 C. to gamma radiation from a C source having an intensity of 3.8 X10 r. per hour to a total dose of about 1 10 1".

After irradiation the fabric was washed and dried under tension. The crease angles of the transparentized unfinished fabric and the finished fabric were as follows:

Unfinished Finished Crease angle:

Warp (deg.) 39 66 Filling (deg) 2O 62 Example 9 2 10 r. The crease angles of the parchmentized unfinished starting material and the resin finished fabric were as follows:

Unfinished Finished Crease angle:

Warp (deg) 14 62 Filling (deg) 11 71 Example The mercerized bleached cotton fabric of Example 8 was treated for ten seconds with a cuprammonium solution containing 18 g. copper, 150 g. ammonia and 10 g. caustic soda per liter, and subsequently freed of copper by treatment with dilute sulfuric acid and then thoroughly rinsed with water. It was after-mercerized with 30 B. caustic soda for fifteen seconds, washed to neutral with water and dried under tension. The thus pretreated fabric was then impregnated with the aqueous aziridinyl phosphonium oxide solution of Example 3, and then dried for ten minutes at 60-70 C. It was thereupon subjected to Co at 20 C. to a total gamma radiation dose of about 1 X 10 r.

The crease angles of the transparentized unfinished material and that of the finished fabric were as follows:

Unfinished Finished Crease angle:

Warp tdcg.) 10 90 Filling (deg) 10 90 Example 11 Urea-formaldehyde precondensate (45%) cc 300 Magnesium chloride g 13 Silicone emulsion g 13 and then squeezed out and without further drying subjected at 20 C. to gamma radiation to a total dose of about 1x10 r., after which it was dried under tension. The crease angles of the transparentized unfinished material and that of the finished fabric were as follows:

Example 12 A spun rayon muslin with 23/21 threads per A French inch and English yarn number 60/70 in the warp and filling was scoured in the usual manner and dried under tension. It was then treated with 47 B. sulfuric acid at 10 C. for ten seconds, washed with water, aftermercerized with 30 B. caustic potash for five seconds, washed to neutral with hot water and then dried under tension. The so pretreated fabric was then impregnated with the urea-formaldehyde precondensate solution of Example 11, squeezed out, dried under tension and subjected at 20 C. to gamma radiation to a total dose of about 1 10 r. This finishing technique resulted in a substantial improvement in the crease resistance of the transparentized fabric.

As a result of the parchmentizing or transparentizing techniques of Examples 812 the tensile strength and elongation at break of the starting fabric are as a rule slightly reduced. However, the irradiation-induced condensation of the condensable substance in accordance with the method of the present invention did not, for all practical purposes, further reduce the tensile or abrasion strength of the transparentized or parchmentized fabric. As respects tensile and abrasion strengths, the finished fabric products of the Examples 8-12 were substantially the same as those of the starting transparentized material, although the crease resistant properties of the transparentized fabric were very markedly improved, as shown. In each example there was improvement in excess of in warp and filling directions.

In each of the above fabric examples the dimensions of the goods following washing did not change for all practical purposes, and the fabrics can be said to exhibit excellent dimensional stability.

While this invention is concerned with an improved finishing method for cellulosic textiles and the improved finished cellulosic textile product it is not to be inferred from the above description or the appended claims that the textile being finished or the finished product consist entirely of natural or regenerated cellulose or a mixture of these cellulosic materials. Cellulosic materials must constitute a major portion of the textile product or textile being finished, but textiles containing in addition a small quantity of non-cellulosic fibers or filaments are also within the scope of this invention.

We claim:

1. A method of finishing a cellulosic textile, which comprises impregnating the textile with a condensable crease-resistance imparting finishing substance dispersed in a fluid carrier and then subjecting the impregnated textile to high energy ionizing radiation to a total radiation dose in the range between about 10 and about 10' r. to condense the condensable substance on the textile without substantially reducing the strength of the textile.

2. A method as set forth in claim 1 wherein the impregnated textile is irradiated at between about 15 and 25 C.

3. A method as set forth in claim 1, wherein the total radiation dose is between about 0.5 10 and about 3 10 r.

4. A method as set forth in claim 1 wherein the impregnated textile is irradiated in squeezed out but moist condition. ,3

5. A method as set forth in claim 1 wherein the impregnated textile is dried prior to irradiation.

6. A crease resistant, cellulosic textile finished by the process of claim 1.

7. A method for imparting wash and wear characteristics to a cellulosic textile material, which comprises impregnating the textile with :a wash and wear resin precondensate in a fluid carrier and then subjecting the impregnated textile to high energy ionizing radiation to a total radiation dose in the range of about 0.5 X 10 to about 3 X10 1'. to condense the resin precondensate without substantially impairing the strength of the textile.

8. A transparentized crease resistant, cellulosic textile fabric finished by the process of claim 7.

References Cited in the file of this patent UNITED STATES PATENTS France Apr. 24, 1956 

1. A METHOD OF FINISHING A CELLULOSIC TEXTILE, WHICH COMPRISES IMPREGNATING THE TEXTILE WITH A CONDENSABLE CREASE-RESISTANCE IMPARTING FINISHING SUBSTANCE DISPERSED IN A FLUID CARRIER AND THEN SUBJECTING THE IMPREGNATED TEXTILE TO HIGH ENERGY IONIZING RADIATION TO A TOTAL RADIATION DOSE IN THE RANGE BETWEEN ABOUT 10**3 AND ABOUT 10**7 R. TO CONDENSE THE CONDENSABLE SUBSTANCE ON THE TEXTILE WITHOUT SUBSTANTIALLY REDUCING THE STRENGTH OF THE TEXTILE. 